Type action



Feb. 20, 19.62 H. 1.. LAMBERT TYPE ACTION 2 Sheets-Sheet 1 Filed Dec.28, 1960 a 5 w w 4 a 3 7 0 0 4 w 5 4 2 2 l 2 3 5 *2 2 )M r 2 Feb. 20,1962 H. L. LAMBERT 3,021,936

TYPEACTION Filed Dec. 28, 1960 Fig.4

2 Sheets-Sheet 2 Y ad.

I v INVENTOR E HARRY LA 5% ATTDRNEYS United; tates fi ment 3,021,936TYPE ACTIUN Harry L. Lambert, West Hartford, Conn, assignor to RoyalMclilee Corporation, Port Chester, N. Y., a corporation of New YorkFiled Dec. 28, 196i), Ser. No. 78,90? 7 Claims. (Cl. 197-17) thisinvention relates to a novel type action for electric typewriters andmore particularly relates to an improved reset arrangement for a powerroll engaging pawl or roll cam which is biased towards a power rollengaging position but which is normally held in a latched position awayfrom a power roll engaged condition.

In type actions where a spring biased member must be reset after theinitiation of an operative stroke of the action it is most common toutilize the kinetic energy of the driven parts to elfect the resettingoperation. Although this resetting action may be reliable it has adisadvantage in that it subtracts varying amounts of kinetic energy fromthe moving type bar linkage and such will affect the intensity of printproduced by the successive typing operations. This condition becomessignificant when it is one of only a relatively low number of variablesaffecting the uniformity of successive type bar speeds.

One object of the instant invention is to provide a novel type actionfor electric typewriters whereby little, if any, of the energy necessaryto reset the power roll engaging pawl to a latched condition is derivedfrom the kinetic energy of the driven parts of the type action.

Another object of the invention is to provide a novel type action forelectric typewriters whereby at least a portion of the energy requiredto reset the power roll engaging pawl is supplied directly from therotating power roll of the typewriter.

Another object of the invention is to provide a novel type action forelectric typewriters whereby two power roll engaging memberssequentially engage said roll during each driving stroke of said action,engagement of the first member serving to cause a driving of the typebar linkage by the power roll and the subsequent engagement of the othermember serving to cause a resetting said first member to an inoperativelatched condition.

Another object of the inveniton is to provide a novel type actionwhereby a power assist is provided for resetting tlie power rollengaging pawl to a latched condition.

A further object of the invention is to provide a novel type action forelectric typewriters whereby the power roll engaging pawl is positivelydriven to an inoperative, relatched condition by the direct drivingaction of the rotating power roll of the typewriter.

Other objects and many of the attendant advantages of this inventionwill be readily appreciated as the same becomes better understood byreference to the following detailed description when considered inconnection with the accompanying drawings in which like referenceumerals designate like parts throughout the figures thereof and wherein:

FIGURE 1 is a side elevational view in partial section and shows thenormal condition of the parts of the instant type action.

FIGURE 2 is a sectional view taken along section line 2-2 of FIGURE 1.

FIGURES 3 and 4 are active views of the apparatus illustrated in FIGURE1.

FIGURE 5 is a side elevational view in partial section and shows amodified embodiment of the instant invention.

Unless otherwise indicated it will be assumed that the various partsshown and described are suitably supported and arranged on the machineframe.

Referring to FIGURE 1 there is shown a type action inc comprising a sublever 15) which is pivotally mounted on a cross shaft 11. The sub leveris articulately connected to the rearward end of an action plate 12 thathas an upper forward end 13 that slidably moves in a slot 14 formed inthe upper part of a comb 15 secured to the typewriter frame member 16.The lower forward end 2i? of the action plate slidably moves in a slot21 formed in the lower part of said comb 15, said end 29 being formedwith two cooperating and laterally bent-off fingers 22. and 23 whichrespectivelyslidably engage the upper and lower adjacent surfaces of thesaid lower part of comb 15 as illustrated in FIGURE 2 thereby permittingonly a rectilinear horizontal sliding movement of the forward end of theaction plate 12. Pivotally mounted on the action plate is a pawl 24having a tooth 25 formed thereon which is adapted to swing intooperative driving engagement with a rotatably driven power roll 26. Thepawl 24 is rotationally biased towards the power roll by means or aspring 27 which is connected between said pawl and a latch 38 that ispivotally mounted on the action plate by means of a stud 31; Therearward end of the latch is formed with a bent off hook 32 whichnormally engages the rearward edge 33 of the pawl so as to maintain saidpawl in a latched or inoperative position away from the power roll asillustrated in FIGURE 1. The forward end of the latch lid is formed witha bent-off shelf 34 which extends through an aperture 35 formed in theaction plate. Disposed immediately above shelf 34 is a lower end 36 of abypass or non repeat dog 37 which is pivotally mounted on a keycontrolled lever 48'. The dog 37 is biased by a spring 41 towards anormal clockwise position determined by engagement of a dog car 42 withthe ad jacent bent over shoulder 43 formed on the key controlled lever40.

A reset lever 44 is pivotally mounted on action plate 12 by means of astud 45. The rearward end of the reset lever is formed with an inclinedcamming edge 46 while the forward end thereof is formed with bent-olfcars 47 and 48 the lower edge of ear 48 normally overlying the upperedge of a forward extending portion 5b of the said pawl 24.

In operation when the type bar associated with the sub lever 10 is to beactuated, the related key controlled lever 40 is operated so that theby-pass or non-repeat dog 37 swings downwardly thereby engaging theshelf 34 of latch 30 and pivoting the latter in a counter clockwisedirection against the action of spring 27. When the hooked end 32 of thelatch moves out of restraining relation with respect to the rearwardpawl edge 33 the pawl 24 will swing in a clockwise direction intooperative driving engagement with the teeth of the rotating power roll26 as illustrated in FIGURE 3. In its engaged FIGURE 3 position the pawl24 through its projection 59 will maintain the reset lever 44 in aclockwise position. After engagement of the pawl and power roll theaction plate 1.2 will be driven to the left in a tangential path withrespect to the power roll as shown in FIGURE 4 so as to drive theassociated type bar towards the typewriter v platen. During the latterpart of the said leftward movement of the action plate 12 the pawl willmove out of engagement with the power roll and the inclined cam edge 46of the reset lever will thereafter engage the outer tips of the counterclockwise moving power roll teeth as illustrated in FIGURE 4 so that thereset lever 44 is then cammed in a counter clockwise direction inresponse to the continued leftward movement of the action plate. Thiscounter clockwise movement of the reset lever will, through the bent offear 48, serve to swing the pawl 24 in a counter clockwise direction backinto latched relation with the hooked end 32 of the latch 30 asillustrated in FIGURE 4. After the power driven printing stroke has beencompleted the type bar actuating linkage is restored to its normalFIGURE 1 position by means of the usual return spring means. Theoperative counter clockwise movement of the reset lever is powerassisted by the frictional contact between the tips of the counterclockwise moving power roll teeth and the reset lever camming edge 46.Thus the energy required to swing the pawl back to the FIGURE 1 latchedcondition is supplied by a combination of the linear inertial effects ofthe leftwardly moving action plate 12 and the frictional effects betweenthe camming edge 46 and the moving power roll teeth. In this manner apower assist directly from the power roll is provided for the resettingof the pawl 24 and such substantially decreases the amount of kineticenergy which must be subtracted from the driven type bar actuatinglinkage for pawl resetting purposes. As a result the fluctuation in theintensity of print of the instant type action is decreased therebyimproving the uniformity of shade and appearance of the typedcharacters.

FIGURE 5 shows another embodiment of the instant invention; here theparts are constructed and operated in a manner similar to that describedin connection with FIGURE 1 except that instead of providing a pivotallymounted reset lever, such as 44 of FXGURE 1, a reset arm 51. is fastenedto the pawl 24, said arm being slightly flexible and having a tooth-likeportion 52 formed at the rearward free end thereof. During the powerdriven stroke of the action plate about the same time that the pawlbecomes disengaged from the power roll the toothlike portion 52 will beengaged by one of the power roll teeth and the latter will thereafterpositively lift the slightly yielding arm 51 so that the pawl is againreset or moved to its latched position shown in FIGURE 5. In this resetaction substantially all of the energy required for resetting the pawl24 is derived directly from the power roll and hence there is little ifany depletion of the kinetic energy of the driven type bar actuatinglinkage for pawl relatching purposes. This condition will furtherimprove the freedom and predictability of movement of the associatedtype bar and such in turn will improve the printing characteristics ofthe type action.

In addition to the above noted advantages gained by power resetting thepawl latch 3% in the manner described, the further benefit of greatlyimproved reliability has been found to flow from restricting the forwardend of the action plate 12 to the rectilinear path of movementdescribed.

While several embodiments of the invention have been shown anddescribed, it will be apparent to those skilled in the art that numerousvariations and modifications may be made in the particular constructionwithout departing from the underlying principles of the invention. It istherefore desired, by the following claims to include within the scopeof the invention all such variations and modifications wherebysubstantially the results of the invention may be obtained by the use ofsubstantially the same or equivalent means.

The invention claimed is:

1. In a type action having a rotating power roll, a type bar actuatinglinkage, a power roll engaging member movably mounted on said linkageand adapted to operatively engage said power roll so as to drive saidtype bar actuating linkage, means for biasing said member towardsengagement with said power roll, and latch means for retaining saidmember in an inoperative position away from said power roll; theimprovement comprising a reset element supported on said type baractuating linkage and having a power roll engaging portion formedthereon, said reset element when engaged with said power roll urgingsaid member towards its inoperative latched position away from saidpower roll.

2. Apparatus as defined by claim 1 wherein said reset element is movablymounted on said linkage and has one portion engageable with said memberand another portion which is formed with an inclined camming edge thatis frictionally engageable with the rotating periphery of said powerroll whereby the frictional action between the power roll periphery andsaid camming edge tends to urge said reset element in a direction whichwill displace said member towards said inoperative latched position.

3. Apparatus as defined by claim 1 wherein said reset element is mountedon said member and has a tooth-like portion which is engageable withsaid power roll so as to substantially positively displace said memberto its inoperative position away from said power roll.

4. In a type action having a rotating power roll, a type bar actuatinglinkage, a power roll engaging member movably mounted on said linkageand adapted to opera tively engage said power roll so as to drive saidtype bar actuating linkage, means for biasing said member towardsengagement with said power roll, and latch means for retaining saidmember in an inoperative position away from said power roll; theimprovement comprising a reset element mounted on said linkage formovement between operative and inoperative positions, and means on saidreset element engaging said member so that when member is held in itsinoperative position the reset element is also held in its inoperativeposition and when said member is unlatched and swings into engagementwith said power roll said reset element will thereby be moved to itsoperative position, said reset element having a camming edge formedthereon which when said reset element has been moved to its operativeposition and subsequently displaced during the power roll driven strokeof said linkage is adapted by reason of the motion of said power stroketo move into camming relation with respect to the power roll so as totend to displace said reset element and said member towards theirrespective normal latched inoperative positions, the frictional contactexistent between the said camming edge and the periphery of the rotatingpower roll during the period that said edge and power roll are incamming relation due to the drive motion of said type bar actuatinglinkage serving to directly assist the displacing of said reset elementand said member towards their said respective normal positions.

5. In a type action having a rotating power roll, a type bar actuatinglinkage, a power roll engaging member movably mounted on said linkageand adapted to operatively engage said power roll so as to drive saidtype bar actuating linkage, means for biasing said member towardsengagement with said power roll, and latch means for retaining saidmember in an inoperative position away from said power roll; theimprovement comprising a reset element secured to said member, saidelement being formed with a power roll engaging toothed portion wherebywhen said member has engaged. and has been power driven by said powerroll said toothed portion will engage said power roll so as to powerdrive said member to its relatched inoperative position.

6. In a type action a type bar actuating linkage including an actionplate, means mounting one end of said action plate for rectilinearsliding movement, a power roll, a pawl pivotally mounted on said actionplate and having a roll engaging portion formed thereon, means forbiasing said pawl towards an operative position in engagement with saidpower roll, latch means for normally retaining said pawl in aninoperative position away from said power roll, and means for resettingsaid pawl to its inoperative position after each power driven rollengaged stroke thereof, said means for mounting one end of said actionplate being arranged to support said pawl for rectilinear movement in apath that is substantially tangential with respect to said power rollwhile said means for resetting said pawl comprises a reset leverpivotally mounted on said action plate and having a roll engagingcamming surface and a pawl engaging projection formed thereon, saidcamming surface being adapted to engage said power roll during a powerstroke and after disengagement of said pawl from said power roll wherebysaid pawl is reset to an inoperative latched position away from saidpower roll.

7. In a type action a type bar actuating linkage including an actionplate, means mounting one end of said action plate for rectilinearsliding movement, a power roll, a pawl pivotally mounted on said actionplate and having a roll engaging portion formed thereon, means forbiasing said pawl in an inoperative position away from said power withsaid power roll, latch means for normally retaining said pawl in aninoperative position away from said power roll, and means for resettingsaid pawl to its inoperative position after each power driven rollengaged stroke thereof, said means for mounting one end of said actionplate being arranged to support said pawl for rectilinear movement in apath that is substantially tangential with respect to said power roll,said means for resetting said pawl comprising an extension formed onsaid pawl and having a toothed portion formed thereon which is adaptedto engage said power roll so as to substantially positively drive saidpawl to its inoperative latched position.

Enders July 28, 1959 Salto Apr. 5, 1960

